The use of visual content, e.g., digital images and video, as a communication modality is becoming increasingly common. Digital photos and videos are frequently captured, viewed, and shared by mobile device applications, instant messaging, electronic mail, social media services, and other electronic communication methods. As a result, large collections of digital visual content exist in and across a variety of different locations, including the Internet, personal computers, and many other electronic devices.
In computer vision, mathematical techniques are used to detect the presence of and recognize various elements of the visual scenes that are depicted in digital images. Localized portions of an image, on which specific types of computations are done to produce visual features, may be used to analyze and classify the image. Low-level and mid-level features, such as interest points and edges, edge distributions, color distributions, shapes and shape distributions, may be computed from an image and used to detect, for example, people, objects, and landmarks that are depicted in the image. Machine learning algorithms are often used for image recognition.